Microwave tomography is a classical approach for non destructive evaluation. Microwave tomography has many biomedical applications such as brain imaging, temperature sensing in different biological tissues and breast cancer detection. In a microwave tomography system, numbers of radiators are used to transmit microwave signal into an object under test and the scattered fields are recorded. The collected data is used to quantitatively reconstruct the dielectric profiles of the object under test through inverse scattering mechanism. It has been shown that by using wide band data, highly stable and high resolution reconstructions can be obtained. Lower frequency components provide stability of the reconstructions, while higher frequency components contribute to the resolution.  Accordingly, ultra wideband antennas are required in UWB microwave tomography systems. In addition to ultra wide bandwidth, the antennas in a microwave tomography system should be easy to model with computational program. In this thesis Printed elliptical monopole antenna (PEMA) is investigated for microwave tomography. It is a multi resonant antenna with simple structure and yield ultra wide bandwidth. The performances of a single antenna and an antenna array are studied. The reflection coefficients of the antenna, mutual coupling between antennas and energy distribution in the near field are obtained by means of simulations in CST microwave studio.    The simulation result shows that reflection coefficients of the designed antenna are below         -10dB over the entire frequency band of interest (1-4.5GHz), mutual coupling between antennas at different locations are below -20dB over the entire frequency band of interest and the designed antenna also has good electric field distribution in an array configuration which makes the radiated power concentrating in the imaging region. These results indicate that PEMA is a potential antenna for microwave tomography applications.

The increased amounts of Internet users, emergence of new technologies that allow content digitization, create an entrepreneurial opportunity for news media to go online. However, the process of digitization has been happening at a different pace in different regions of the world. To understand the keys to success and to learn on mistakes, it is important to understand what are the factors that affect entrepreneurship and digitization of news media. The purpose of this study is to investigate the news media sector in Russia in terms of digitization of the newspaper content and entrepreneurial activities associated with this. After conducting a case study on online newspaper Novaya gazeta in Russia, authors conclude that transition economy factors have an impact on digitization of newspapers in Russia. Specifically these factors are state’s involvement in the business sector, political and economical conditions in the market and risk- averse entrepreneurs who run newspapers in transition economies. / Uppsök subject category: Business Administration; Economics

Increasing demands for more reliability and functionalities in electronic devices have pushed the electronics industry to adopt newly developed materials and reduce interconnect sizes and spacing. These adaptations have led to concerns of reliability failures caused by conductive anodic filament formation (CAF). CAF is a conductive copper-containing salt that forms via an electrochemical process. It is initiated at the anode and grows along the epoxy/glass interface to the cathode, and once CAF reaches the cathode a short circuit will occur. The objective of this research is to evaluate and compare the effects of curing agents (DICY vs. phenolic-cured epoxy) and drilling methods (laser vs. mechanical drilling) on CAF formation using an insulation resistance test at 85 ºC, relative humidity of 85%, and a voltage gradient of 0.4V/µm. Time-to-failure for DICY-cured and phenolic-cured epoxy with laser drilled microvias and mechanically drilled vias were determined using the insulation resistance test. The failed coupons were cross-sectioned and examined using a Scanning Electron Microscope equipped with Energy-dispersive X-ray spectroscopy to verify the existence of CAF. Weibull analysis was used to compare the reliability and identify the failure modes of the failed coupons. Test results show that DICY-cured epoxy is a better CAF resistant material than phenolic-cured epoxy. It is believed that the brittleness of phenolic-cured material might enhance the damage to the epoxy/glass fiber interface during drilling; and hence, facilitate subsequent CAF formation. The study also shows that laser drilled microvias are less prone to CAF formation than mechanically drilled vias, because there is less mechanical damage and lower glass fiber content. Finally, using Weibull analysis, it is determined that laser drilled microvias experienced infant-mortality failure, whereas mechanically drilled vias exhibited a wear-out type failure.

This work aims to improve our knowledge about Swedish video game journalists, a new occupation in a quickly expanding business. Through a survey sent out to over 50 Swedish video game journalists, the result indicate some unexpected facts. Men largely dominate the profession; just 10 % of the work forces are females. This relation was notable in our survey, as well as in earlier studies. Video game journalists between 26 and 35 years old seems to be the largest age group, which we think is a bit surprising considering how new this form of journalism is, and the fact the internet provides opportunities for every enthusiastic video game writer. The professionalism of video game journalists has been debated over a long time, with many people arguing that this type of work has little to do with traditional journalism. In our survey, a large part of the respondents made clear that they consider themselves to be writers rather than journalists. The majority of the Swedish video game journalists don't have a journalistic education, whether it's from high school or university. Most of them don't value education as much as writing skill, talent, passion and knowledge about video games. The minority arguing about the importance of education motivates their standpoint with arguments of classical journalistic ethics and values. One respondent told us that the whole industry would benefit from more highly educated journalists, another one pointed out that a lot of ground has been covered in the last 5-6 years, although there ́s still a great distance compared to traditional journalism.

This thesis is a qualitative study in which 12 award-winning printed adverts, awarded with either a Swedish “Guldägg” or an international Clio Award, have been analyzed from a rhetorical perspective. Visual rhetorics were used to analyze the adverts in order to expose the rhetorical concepts and to find out whether the rhetorical concepts represented in the Swedish adverts are the same concepts represented in the international adverts. One of the conclusions drawn is that pathos-arguments, a rhetorical concept where the senders allude to the emotions of the receivers, are the most prominent in both Swedish and international adverts, but are used in different ways. Another conclusion drawn is that the adverts are overall characterized by their messages not being explicit. This is a rhetorical concept being used in order to stand out in today’s media flow.

Cast multi-crystalline silicon substrates are used in more than 50% of the photovoltaic modules produced today. The random grain orientations of multi-crystalline silicon wafers inhibit the formation of an effective surface texturing using conventional techniques. The other main substrate used is single crystalline Czochralski wafers (~30% of the market share). Czochralski silicon material is known to suffer from the formation of a metastable defect under carrier injection, sometimes referred to as light induced degradation (LID). Light induced degradation in low-cost photovoltaic grade silicon is studied. Trap formation is shown to occur at temperatures above 200oC. Efficiency degradation reduced from 0.75% to 0.24% when the cell thickness was reduced from 378 to 157m. The presence of light induced degradation in ribbon silicon solar cells is documented for the first time in this thesis. Trap generation and annihilation are observed in high lifetime regions of multi-crystalline silicon samples. No degradation was observed over a 24-hour period at 25oC in high efficiency ribbon solar cells (>16%), but at an elevated temperature of ~75oC, appreciable efficiency degradation was observed. Czochralski silicon solar cells showed full degradation within 24 hours at 25o C. Part two of this thesis involves the development of a surface texturing suitable for all crystalline silicon. Only 6 to 10 seconds in a 200:1 HF to HNO3 solution at room temperature allows for the formation of an effective porous silicon anti-reflection coating. This resulted in a porous silicon anti-reflection coated solar cell efficiency of 15.3% on a float zone Si sample with an excellent fill factor (78.7%). The typical process used in the literature involves porous silicon etching as the final step in the solar cell fabrication sequence. The major problem associated with this process sequence is fill factor degradation. This problem was overcome in this research by porous silicon etching prior to cell processing. It is shown that incorporating an acid texture prior to porous silicon etching can improve the surface reflectance for cast multi-crystalline and Czochralski silicon samples. Solar cell efficiencies of 14.8% for Cz Si and 13.6% for cast mc-Si were achieved.

Novel printed slot antennas are demonstrated in this thesis. For the linear polarization design, CPW-fed strip-loaded square slot antenna is presented for achieving broadband operations. For the circular polarization, two novel antenna designs are also presented¡Fone is a CPW-fed square slot antenna with an inverted L tunning stub, and the other is a microstrip line-fed square slot antenna with a conducting strip from ground plane for broadband circularly polarized radiation. Finally, an antenna design having compact size and broadband characteristic is shown.

Flexible printed circuits (FPCs) have a flexible character, so the topic for high accuracy and speed of drill is important. We will create an automatic system that joins vision-guided function to accomplish the challenge object of high quality and low cost. The system must contain two sub-systems, which are the machine position control and the image recognition. The machine position control system basis framework moves to position after getting hole-position with different methods and scheme of trajectory planning. The image recognition system framework exports correction to machine position control system that integrates the technique of charge-coupled device (CCD), light source design, snap an image in region of interest (ROI) with image grabber card, pattern match that uses normalized cross correlation (NCC) algorithm. We can proof that the system can achieve the expected goal of high speed and accuracy of drill.

Several novel designs of printed monopole antennas are proposed and experimentally studied. These antennas have the advantages of low profile, light weight and easy construction and can be printed on dielectric substrates and integrated with associated circuitry on the same substrates, which not only reduces the manufacturing cost but also decreases the required size of the complete system. This dissertation mainly consists of four sections and several novel designs are introduced in each section. First, a novel dual-band antenna with two stacked inverted-F strips and a CPW-fed folded inverted-F strip antenna are proposed. Second, a novel printed dual-band double-T monopole antenna, comprising two stacked T-shaped monopoles, is discussed. Third, three diversity antenna designs obtained by protruding a ground plane with optimal dimensions between two printed monopoles for WLAN communication applications in the 2.4 GHz and 5.2 GHz bands are presented. Good dual-polarized radiation with an enhanced port decoupling (isolation less than ¡V27 dB) for the two feeding ports is obtained. Finally, a novel printed ultra-wideband diversity monopole antenna is shown. The operating bandwidth of the ultra-wideband antenna reaches about 5.4 GHz, covering the WLAN bands at 2.4, 5.2 and 5.8 GHz, and the antenna can provide spatial diversity to combat the multipath fading problem.

Abstract One of the features in Taiwan market is price competition. What makes it even worse are the outflow of investment, more demand on environmental protection, increase of labor cost, and the limit of national policy. These factors make business hardly earn profits. And therefore, how to gain reasonably with limited resources and survive in the competition are the difficulties we need to overcome in Taiwan. Printed Circuit Board played a key role in ¡§Taiwan Financial Miracle¡¨ for the past 10 years. However, the manufacturers now have no choice but to search for new niche to meet the change on the whole business environment. The headquarters staying in Taiwan have to face even more harsh conditions, which come from the demand of cost-down, the price competitions among the same industry. Therefore, it becomes essential to adjust Product Mixed in order to fit the insufficient Product Resources. My study puts focus on ¡§Most Constrained Station¡¨ from the Theory of Constraint. It helps PCB manufacturers, who suffers slim profit, find out the best Products Mixed in accordance of Throughput Contribution. Each product brings different profit and cost. Some may share common resources, and some may not, when they are put in the process line. Therefore, to continue forward in the age of slim-profit, the complex of Product Mixed and earnings becomes prominent. Studying Theory of Constraint, I aim to bring forth the best solution on processing contribution by means of figuring out the Throughput Chain in Most Constrained Station and analysis of application on Most Constrained Station. And then I will conclude with the best production strategy for the PCB manufacturer as the main thesis of the research.